Match!

Inhibition Mechanism of Phosphate Ions on Chloride-Induced Crevice Corrosion of Alloy 22

Published on May 1, 2015in Corrosion1.865
· DOI :10.5006/1373
Marcela Miyagusuku2
Estimated H-index: 2
,
Ricardo M. Carranza10
Estimated H-index: 10
,
Raul B. Rebak19
Estimated H-index: 19
Abstract
Alloy 22, a nickel-based alloy that belongs to the Ni-Cr-Mo family, shows an outstanding corrosion resistance in most environments. Alloy 22 was extensively studied regarding its crevice corrosion behavior both in pure chloride solutions and in solutions containing other ions such as nitrate, sulfate, and carbonate/bicarbonate. Electrochemical tests were performed to study uniform and localized corrosion of Alloy 22 in a deaerated aqueous solution of 1 M NaCl and 1 M NaCl with different amounts of phosphate additions at 90°C and at pH near neutral. Results show that the addition of phosphate to the solution increased the length of the passive potential range. Moreover, results from two type of electrochemical tests showed that the addition of 0.3 M phosphate and higher completely eliminated the susceptibility of Alloy 22 to crevice corrosion. The excellent inhibitive effect of phosphate is comparable to that of nitrate already reported in the literature. Elemental analysis of the corroded area suggests th...
  • References (40)
  • Citations (4)
📖 Papers frequently viewed together
19881.86Corrosion
18 Citations
20041.86Corrosion
7 Authors (S. D. Day, ..., Raul B. Rebak)
10 Citations
2017
78% of Scinapse members use related papers. After signing in, all features are FREE.
References40
Newest
10 CitationsSource
#1M. Rincón Ortíz (CONICET: National Scientific and Technical Research Council)H-Index: 3
#2M.A. Rodríguez (CONICET: National Scientific and Technical Research Council)H-Index: 3
Last. Raul B. Rebak (GE: General Electric)H-Index: 19
view all 4 authors...
Abstract Oxyanions were tested as inhibitors of the chloride-induced crevice corrosion of Alloy 22, at 90 °C. Nitrate was the most efficient inhibitor showing R CRIT = 0.2 for the two tested chloride concentrations. Sulphate showed R CRIT values of 1 and 2 in 0.1 mol/L and 1 mol/L NaCl solutions, respectively. Carbonate showed R CRIT = 1 while bicarbonate and carbonic acid did not show any inhibiting effect. Chromate and molybdate showed R CRIT = 0.5 in 0.1 mol/L NaCl solutions being less effect...
22 CitationsSource
#2C. Mabel GiordanoH-Index: 4
Last. Raul B. Rebak (GE: General Electric)H-Index: 19
view all 5 authors...
Abstract The crevice corrosion kinetics of alloys C-22, C-22HS and HYBRID-BC1 was studied in several chloride solutions at 90 °C. The crevice corrosion resistance of the alloys increased with PREN (Pitting Resistance Equivalent Number), which is mainly affected by the Mo content in the alloys. The crevice corrosion kinetics of the three alloys was analyzed at potentials slightly higher than the repassivation potential. Crevice propagation was controlled by ohmic drop in the more dilute chloride ...
42 CitationsSource
#1Pellumb Jakupi (UWO: University of Western Ontario)H-Index: 13
#2Fengping Wang (USTB: University of Science and Technology Beijing)H-Index: 5
Last. D.W. Shoesmith (UWO: University of Western Ontario)H-Index: 26
view all 4 authors...
Abstract Surface analytical techniques were applied to characterize corrosion products formed during the crevice corrosion of the Ni–Cr–Mo(W) Alloy-22 in 5 mol/L NaCl at 120 °C. Micro-Raman spectroscopy demonstrated the formation of polymeric molybdates within the crevice corroded region where intergranular corrosion dominated. The location and chemical speciation of the Mo and W species formed was investigated by Raman mapping. Crevice corrosion was found to propagate preferentially across the ...
44 CitationsSource
#1C. Mabel GiordanoH-Index: 4
#2M. Rincón OrtízH-Index: 3
Last. Raul B. Rebak (GE: General Electric)H-Index: 19
view all 5 authors...
AbstractAlloy 22 (UNS N06022) belongs to the Ni–Cr–Mo family, and it is highly resistant to general and localised corrosion; however, it may suffer crevice corrosion in aggressive environmental conditions. The susceptibility to crevice corrosion is measured by the value of the repassivation potential. The objective of this work is to compare different electrochemical methods for determining the repassivation potential of alloy 22; these include cyclic potentiodynamic polarisation, Tsujikawa–Hisa...
21 CitationsSource
#1M. Rincón OrtízH-Index: 3
#2Mirtha RodríguezH-Index: 4
Last. Raul B. RebakH-Index: 19
view all 4 authors...
Abstract Ni-Cr-Mo alloys are highly resistant to general and localized corrosion, but they may suffer crevice corrosion in aggressive environmental conditions, such as high-chloride concentrations,...
31 CitationsSource
Abstract One important factor affecting crevice corrosion of passive metals is the crevice geometry, e.g., the gap of the crevice. The crevice geometry can be affected by the properties of the materials used as the crevice formers, i.e., a polymeric crevice former can conform to the surface roughness of a metal specimen, which helps the creation of a tighter crevice gap. The objective of this work was to investigate the effects of crevice former materials on the evolution of crevice corrosion da...
9 CitationsSource
#1Florent Bocher (UVA: University of Virginia)H-Index: 8
#2R. HuangH-Index: 2
Last. John R. ScullyH-Index: 33
view all 3 authors...
Abstract Critical potentials for crevice corrosion initiation were predicted for Ni-22Cr-XMo alloys (X=0,3, 6, 9, 13%), Alloy 625 (UNS N06625), and Alloy 22 (UNS N06022) based on electrochemical ox...
18 CitationsSource
#1Martén A. Rodríguez (National Atomic Energy Commission)H-Index: 2
#2R M CarranzaH-Index: 4
Last. Raul B. RebakH-Index: 19
view all 3 authors...
Abstract Alloy 22 (UNS N06022) is a Ni-Cr-Mo alloy, highly resistant to localized corrosion. It has a wide range of industrial applications. Because of its versatility, Alloy 22 has been proposed a...
22 CitationsSource
#1Xi Shan (Case Western Reserve University)H-Index: 5
#2Joe H. Payer (Case Western Reserve University)H-Index: 18
The crevice corrosion performance of Alloy 22 was tested under potentiostatic polarization more positive than the repassivation potential in 4 M NaCl solution at 100°C. Under this aggressive condition, crevice corrosion initiated under the crevice contacts and four stages of corrosion behavior were observed: initiation, propagation, stifling (corrosion slowed), and arrest (corrosion stopped). During the exposure, dark green deposits were found on the uncorroded metal surface around the crevice c...
23 CitationsSource
Cited By4
Newest
#1Jeffrey D. Henderson (UWO: University of Western Ontario)H-Index: 5
#2N. Ebrahimi (UWO: University of Western Ontario)H-Index: 8
Last. James J. Noël (UWO: University of Western Ontario)H-Index: 23
view all 6 authors...
Abstract Coupling of metal oxidation in crevice corrosion to both O2 reduction on surfaces external to the crevice and H+ reduction occurring within the crevice, was studied using a galvanostatic crevice corrosion technique in conjunction with weight loss analyses. Results suggest internal H+ reduction is a significant contributor to the crevice corrosion of the studied alloys in 5 M NaCl at 120 °C. Repeat experiments suggest damage can be as much as doubled by H+ reduction. This process, howeve...
5 CitationsSource
The effect of elevated temperature has on the hydrate shell of a singly charged sodium cation inside a flat nanopore with smooth walls is studied using the Monte Carlo method. The free energy and the entropy of vapor molecule attachment are calculated by means of a bicanonical statistical ensemble using a detailed model of interactions. The nanopore has a stabilizing effect on the hydrate shell with respect to fluctuations and a destabilizing effect with respect to complete evaporation. At the b...
Source
#1R M CarranzaH-Index: 4
Nickel-based alloys are considered among other candidate materials as engineering barriers of geological repositories due to their excellent corrosion resistance. These alloys possess unique advantages: they may be used in saturated and unsaturated repositories, hosted by practically any rock type, while also compatible with any (or no) backfill, and have minimal impact in other barriers. Alloy-22 (UNS N06022) has been the most studied of this class of alloys for its potential application in the...
6 CitationsSource
#1Helmuth Sarmiento Klapper (BHGE: Baker Hughes)H-Index: 4
#2Natalia S. Zadorozne (CONICET: National Scientific and Technical Research Council)H-Index: 3
Last. Raul B. Rebak (GE: General Electric)H-Index: 19
view all 3 authors...
There are a great variety of commercial nickel alloys mainly because nickel is able to dissolve a large amount of alloying elements while maintaining a single ductile austenitic phase. Nickel alloys are generally designed for and used in highly aggressive environments, for example, those where stainless steels may experience pitting corrosion or environmentally assisted cracking. While nickel alloys are generally resistant to pitting corrosion in chloride-containing environments, they may be pro...
4 CitationsSource